Device for separating carbonaceous materials



March 21, 1939,. J R. BELKNAP DEVICE FOR SEPARATING CARBONACEOUSMATERIALS 3 SheetsSheet 1 Filed July 27, 1937 INVENTOR. Josz. A? BELKN/JP ATTORNEY.

March 21, 1939.

J. R. BELKNAP DEVICE FOR SEPARATING CARBONACEOUS MATERIALS Filed ,July27, 1937 3 Sheets-Sheet 2 QU-IZUZZ INVENT OR BY JOEL. A. BELKA/HP XATTORNEY.

March 21, 1939. J. R. BELK NAP DEVICE FOR SEPARATING CARBONACEOUSMATERIALS Filed July 27, 1957 5 Sheets-Sheet 5 INVENT OR. JOEL 7?.BELKN/IP Patented Mar. 21, 1939 DEVICE FOR SEPARATING CARBONACEOUSMATERIALS Joel R. Belknap, South Charleston, W. Va.

Application July 27., 1937, Serial No. 155,958

4 Claims.

The invention relates particularly to mechanism adapted for separatingcarbonaceous materials. My copending application Serial Number 48,388 isintended for similar purposes. Hereto- 5 fore many different methods andkinds of apparatus and mechanism have been used for separating coal fromslate, and other refuse in coal,

some of which utilize the difi'erences in specific gravities in thecomponent parts of the aggregate run of mine coal. Others of themutilize a liquid having a relatively high specific gravity, whereby therelatively light weight coal will float on the surface and the heavierslate and other refuge will sink to the bottom of the liquid, becausethe specific gravity of the liquid is greater than the specific gravityof the coal but less than the specific gravity of the slate and otherrefuse. Such methods which utilize this latter method. known asfloatation processes, are slow in opera- 20 tion and the cost ofequipment and subsequent operation is relatively high.

Other classifications of methods and apparatus are utilized to effect aseparation of coal from slate, and other refuse in coal, by passing acur- 25 rent of water through compact masses of coal, causing theheavier slate and refuse to segregate and collect at the lower part ofthe whole mass, from which they are separated by specially designedmechanism. However, in many such 30 methods the separation is not aseffectivev as in my method, and by use of my apparatus.

From experimentation and actual practice, I have determined that therelative differences in the velocities of sinking components of coal and35 refuse is greater than indicated by a mathematical comparison of thespecific gravities and velocities of sinking coal and refuse. Forillustration, if a piece of coal which has a specific gravity of 1.4 isplaced in water, the force acting to sink the coal is proportional to1.4 less 1.0, or .4. If the coal is placed in a liquid having a specificgravity of 1.2 the sinking force is proportional to 1.4-1.2, or .2 whichis half the force acting to sink the coal in water. Similarly considerrefuse 45 (for example slate) having a specific gravity of 2.6, thesinking force in water is 1.6 and in liquid having a specific gravity of1.2 is 1.4. Thus the sinking ratio as between refuse and coal would be50 in water and in a liquid of 1.2 specific gravity. This larger ratiofavors clean separation, particularly where the forms and specificgravities of the granules to be separated are subject to variation.However, actually the difference, when compared with coal and refuse, isappreciably greater, because refuse, such as slate, usually is fiat orstreamline, whereas coal usually is of cubical shape, or somewhatspherical.

Using the term "rising current classification as meaning classificationeffected through the different settling rates of granular particles ofdifferent specific gravity, (or of different shape and specific gravity)in a rising stream of liquid, it 0 will be observed that thedifferentiation of settling rate can be intensified by using a liquidwhose specific gravity is less than, but only moderately less than thespecific gravity of the particles of lower specific gravity. Thisconcept is an important feature of the present invention. Strictflotation requires solutions too concentrated for successful commercialuse, but it is entirely practicable to use the relatively dilutesolutions needed for a rising current process.

My invention differs particularly from the floatation methods because Iutilize a liquid having a specific gravity less than the lightest com-'ponent of coal. Therefore, my liquid has a specific gravity of less thanthe heavier components slate and other refuse. My utilized liquid rangesin specific gravity from a maximum point which is less than the specificgravity of the lightest component of uncleaned coal to a minimumdetermined by economic considerations afiected by the problem ofmaintaining the concentration of the solution, etc., for the device willoperate with water, but not so advantageously.

Another important difference between my process and apparatus and thepast art is that the coal, as it comes from the mine, is not treated ina mass, but each piece of coal or refuse, or piece of coal containingrefuse, is acted upon separately and sinks in an individual pathdepending on its size, specific gravity and shape. In other words, 40the device operates on the rising current principle, and is sharplydistinguished froma jig.

Also, I provide a container for said liquid which has two compartments,communicating with each other. One of said compartments contains refuseand the other said compartment contains sinking coal and refuse. Icontrol the sinking velocity of the coal and refuse, as slate, byproviding adjustable means which can be regulated to vary the velocityof upward currents of liquid from one compartment and into the other andthrough which currents coal and refuse is sinking and, at the same time,cross or transverse currents are produced in the liquid in one of saidcompartments for the purpose of transporting the coal,

which sinks at a lesser velocity than the refuse,

' to a predetermined area or to mechanism adapted refuse in coal byallowing the particles to sink.

through two currents which combine to create a current of liquid whichmoves vertically and horizontally, said liquid being lighter in specificgravity than the lightest component of the aggregate whereby the heaviercomponents shall deposit in a predetermined space and the lightercomponents shall deposit in a different space; to provide mechanism toconvey said coal and slate; and to provide means to produce upward andhorizontal currents of said liquid and to regulate the velocity of saidcurrents.

Other objects of the invention are apparent by reference to thehereinafter description, and drawings.

The invention consists in the combination of the elements, arrangementof the parts and in the details of the construction, as hereinafterfully explained.

In the drawings:

Fig. 1 is a side view of the container, and mechanism with parts brokenaway, having the invention incorporated therein;

Fig. 2 is a plan view of the same, with parts broken away, and showingthe invention incorporated therewith; I

Fig. 3 is a section taken on a line corresponding to 8-8 in Fig. 2 withparts broken away;

Fig. 4 is a section taken on a line corresponding to 44 in Fig. l, withparts broken away;

Fig. 5 is a section taken on a line corresponding to 55 in Fig. 1;

Fig. 6 is a fragmentary side elevation at the discharge end of the tank,with parts removed and broken away, showing the mechanism forcontrolling the flow of water and solution;

Fig. 7 is a side elevational view of a sprocket, or pulley, andconveyor, with parts broken away;

Fig. 8 is a diagrammatic view of the conveyor drives; and

Fig. 9 is a plan view of the valve mechanism, and tank with parts brokenaway.

In the preferred construction of the invention I provide the tank orcontainer I which is supported by the platform 2, and supports 2.

The tank I has a horizontal bottom 8 and vertical side walls 4 and 5rising from thebottom and integrally connected therewith. The inlet endwall 6 inclines upwardly and outwardly at an obtuse angle with respectto the bottom and is integrally connected with the side walls 4 and 5.The outlet end wall I is integrally connected with the bottom and sidewalls.

Formed in the bottom 8, of the tank I, is the trough 8 which extendstransversely and across the tank. The width of the opening 8 of the opentop of the trough and its location is predetermined by calculation andin consideration of all the factors involved in the operation of theinvention. As will be hereinafter explained the trough 8 receives theheavier or impure components of the mined coal, as slate, rock, andother impurities, which will be referred to as refuse 9,

which are separated from the pure coal III. A screw conveyor II ispositioned in and operates in the trough 8 to convey the refuse to theoutside of the tank I. The shaft I2, which revolves the conveyor I I,has one end I8 joumaled in the end wall I4 of. the trough 8.

On the side wall 4 of the tank I is secured a conveyor casing I5 and thelower end thereof opens into the discharge end I8 of the trough 8. Thecasing I5 is inclined upwardly from the trough 8 to the discharge end ofthe tank, and forms a water-tight chamber from the trough 8 to a pointabove the liquid level in the tank where it is open to receive theendless refuse conveyor I! which travels in the casing I5. The screwconveyor shaft I2 has an extension on the end I8 journaled in the endwall I8 of the trough 8. On this extension is rotatably mounted thelower sprocket pulley 20 about which the lower end of the refuseconveyor belt 2I, of the conveyor I1, is trained. There are transversecleats 22 on the conveyor belt 2I which wipe against the bottom inclinedwall 28 of casing I1 and slide the refuse 8' up the inclined wall 28.The refuse is pushed into the casing I! by the screw conveyor I I. Theconveyor conveys the refuse up the bottom of the casing and dischargesthis retuse into the chute 24 which is separate from the discharge chute25 for the coal I0.

The shaft 28 is journaled in a bracket 21 at one end and in the bracket28 at the other end. This shaft 28 has a pulley 28 thereon similar tothe pulley 20, and about this pulley 28 is trained the upper end of therefuse conveyor I'I.

Fixed to the upper end of the discharge end wall are aligned bearingbrackets 29 and 88in which are iournaled the ends of the shaft 8I, onwhich is secured a sprocket pulley 82, around which is trained the upperend of the endless coal conveyor 88. The shaft 8I drives the coalconveyor 88 in a direction opposite to the refuse conveyor II. The lowercoal conveyor sprocket pulley 84 is fixed to a shaft 85, the ends ofwhich are journaled in the side wall 5 of the tank. The conveyor 88 isperforated and has substantially the same width as the tank I.

As the pure coal III sinks through the liquid 84 in the tank I itdeposits on the upper flight of the conveyor 88 at the lower end, aswill be hereinafter explained, where it is carried upwardly on anincline and discharged over end wall I and into the coal chute 25, at apoint separate from the refuse.

Extending transversely of the tank I, at the 'over the tank. Water issprayed on the coal from this pipe 86 as the coal emerges from the tankand the coal is washed. Moreover, a portion of the liquid 84 whichadheres to the coal is thereby returned to the tank.

For the purpose of causing an internal movement of the liquid 84 in thetank I an apron or bridge wall 81 is provided which extends across thetank with flanges 88 on the sides thereof bolted to the side walls 4 and5 of the tank. The bridge wall is located at the end of the conveyor 88and above the vertex of the obtuse angle formed between the outlet endwall I and the bottom 8 of the tank. The impeller chamber 89 is formedas by the end wall 48, and the upper and lower horizontal walls 4I and42. The end 48 of the wall H is connected with the bridge wall. 81 andthe end 44 of the wall 42 is connected with the outlet end wall I. Theother ends of the walls 4| and 42 have connected therewith the verticalend plate 45 in which is journaled the propeller shafts 46 and 46'having fixed to their ends 41 the propellers 48 and 48. The other end ofthe shaft 46 has a wheel 48 and a pulley 58 fixed thereto. The wheel 49is in contact with the wheel 5| which is connected with and operated bythe usual electric motor 52 supported by the support 53 which is mountedupon the platform 2. 1 1

The shaft 46' has a pulley 58' thereon which is in alignment with thepulley whereby a belt 53 causes rotation of the shaft 46 and pulley 50',when the Wheel 5| imparts rotary movement to the wheel 48, shaft 46 andpropeller 48.

In relatively small tanks only one impeller is necessary but in theapparatus illustrated a pair of propellers are shown. An intermediateportion of the impeller shafts 46 and 46' are journaled in water-tightbearings 54, in the end plate 45, and the outer portion of these shaftsextends outwardly of the tank.

The tank I has two compartments, the upper compartment and the lowercompartment 56. The compartments are divided by the partition 51 whichcomprises the buttress plate, or side, 58, the apron or bridge wall 31,and the upper flight of the conveyor 33 which has the spaced apartperforations 59 therein to permit liquid to drain from the coal into thetank 'I. The opening or separating slot or passage68 is provided in thepartition 51 and which is a passage for refuse, as will be hereinafterexplained.

For the purpose of insuring that the heavier components of the aggregatewill fall into the trough 8, in the event that there is not completecoordination of the operating elements, such as sudden changes in therate of raw coal feed, specific gravity of the liquid, or other suchfactors, the buttress plate or side 58, which bridges the width of thetank I, is positioned adjacent the inlet end wall 6 and arranged toswing on horizontal pivot bolts 6|, one for each side of the plate. Theends of these bolts are anchored to the side walls 4 and 5. These bolts6| extend through apertured ears 62 fixed to the upper corners of theplate. The plate 58 extends the major portion of the depth of the tankand terminates at a point substantially in alignment with the upper halfof the bottom sprocket pulley 20 so as to be aligned with the lower endof the upper flight of the conveyor 11.. All coal and refuse falling onthe plate 58 are directed toward the passage 68.

The angle of plate 58 may be adjusted by the I use of a bolt 63 having athreaded intermediate portion extending through a slightly elongatedaperture in the end wall 6 and threadably engaged by a pair of nuts 64,one bearing on each side of the end wall 6. The inner end of the bolt 63extends through an opening in the plate 58. A pair of nuts 65 aremounted on the inner end of the bolt 63, one bearing on each side of theplate 58. Thus by changing the gripping positions of the nuts 64, theangle of the plate 58 may be changed as desired.

Fixed to the lower end of the wall 48 is the plate 40' which has-aplurality of slots 40" therein. The plate 40 is inclined downwardly andtoward the outlet wall 1.

Due to the rotatable movement of the propellers 48 and 48', the liquidis caused to move, and

' a current is created in the liquid. For the reason compartments 55 and56, and the current of liquid is created in the lower compartment 56,this current must travel through the perforations 48 in the plate 40,and below the plate 40' and then upwardly through the passage at a rateof speed dependent, and capable of being regulated, upon the revolvingspeed of the propellers 48 and 48' and the width or area of the passage68. The position of the hinged plate 58 controls the area of the passage60, W1 ereby if the plate 58 is raised the area of the passage isreduced and thawlocity of upward current of liquid, in consideration ofthe propellers having a regular rotatable speed, is increased. On theother hand, if the plate 58 is lowered the area of the passage 68 isincreased and, since the area of the path of the current of liquid isincreased, the speed or velocity of the current is decreased. Obviously,with the passage 60 having a predetermined area, or width and length,the velocity of the current of the liquid which passes upwardly throughthe passage 60 can be increased or decreased by varyingthe rotatablespeed of the propellers.

Now it is obvious that not all of the currents, or agitated liquid, passthrough the passage 60, whereby a secondary current of the liquidtravels past the passage 60 and contacts the inlet wall 6 and isdeflected upwardly and in contact with the plate 58. This lattermentioned or secondary current carries liquid through the perforationsin the plate 58 and after this secondary current passes through theperforations, and through the coal and refuse on the plate 58, thissecondary current drifts or moves horizontally or toward the outlet end1 of the tank I and meets the upward current which previously has passedthrough the passage 60. The meeting of the up ward current with thehorizontal current produces a current or drift of the liquid in adirection which is substantially at an angle upwardly and toward theoutlet wall or end 1 of the tank.

Since the specific gravity of the pure coal is only moderately greaterthan the specific gravity of the liquid, the lifting effect of theupward current of liquid keeps the coal in suspension for a considerabletime. -This action can be modified by varying the specific gravity ofthe liquid or by varying the velocity of the rising current, but in anyevent, the coal which remains in suspension after it leaves the supplychute is kept in suspension until the cross-current produced by fiowthrough the perforations 65 in the plate 51 carries the coal over thebarrier 31. Refuse settling on the plate 51 will slide to the throat,and if any coal should be trapped with the refuse and slide with it tothe throat it will be elevated by the rising current and carried overthe barrier 31. Consequently, while the separation occurs almostexclusively with the coal in suspension, any coal which may move to thethroat over the plate 51 together with the settling refuse, will berecovered by being again brought into suspension in the zone where therising current of liquid is most active.

The liquid 34 substantially fills the tank to the level indicated at 61.This liquid may vary in specific gravity within the limits of pure waterand a liquid having a specific gravity equal to the specific gravity ofthe lighter component coal. When it is desired to increase the specificgravity of the liquid above water any of the cheaper grades of saltsthat will not disintegrate the coal or adversely effect its burningproperties may be used. Common salt or sodium chloride has been usedwith excellent result, as well as calcium chloride, magnesium chloride,or any of the salts of the alkali earth metal group taken separately orin combinations, depending on their relative economy and desiredeffects.

It is, of course, advantageous to maintain a substantially constantpredetermined density or specific gravity of the liquid in tank I and tocompensate for the volume absorbed by the refuse 8 and the coal I8, saltor other materials heretofore mentioned is automatically introduced forincreasing the density, either in granular or concentrated liquid formthrough conveyor pipe 68 by any suitable pressure, gravity or otherwise.This pipe 68 deposits the liquid or granular material in the tank abovethe liquid level 61 thereof. In the pipe 88 is a control valve 68 havinga lever 10 to turn the valve.

On the wash-water pipe 88 there is a control valve 1| outwardly of theperforated end that is positioned over the tank. On one side wall I oftank I is a bracket 12 to which is pivoted as at 13 the apex of a bellcrank lever and one leg 14 of this lever is formed with a series ofopenings 15 continuous with its length. The other leg 16 of this leverhas the free end pivoted at H to an upstanding arm I8 on the float 18.The float moves as the liquid level 84 in the tank varies.

The valve arm 18 is connected by a link rod 88 to any predeterminedpoint on the arm H by a bolt 8| inserted in the selected opening of theseries 15.

series of openings 15 on the arm 14. The variation of the liquid levelis therefore transmitted through the fioat 18, the bell crank 18, linkrods 80 and 82, to the water valve II and the density increasingmaterial pipe valve 88. Since the stroke of the link rods 88 and 82 maybe regulated, and these link rods move in response to the variation ofthe liquid level in the tank, the volume of water and the densityincreasing material may be controlled.

Any suitable means may be used to drive the conveyors 88 and I1, and inFig. 2 is shown the electrically operated motor 88 which has the drivingshaft 84 on which is connected the gear 85 and the sprocket 88. On thesprocket 86 is meshed the chain 81 which is meshed with the sprocket 88fixed to the shaft 8| which operates the conveyer 88 by means of thesprockets 82.

Fixed to the end of the shaft 84 is the gear 85 which meshes with thegear 88 fixed to shaft 88 which is fixed to the casing ID, as by thebolts 8| and 82. On the shaft 88 is the sprocket 88 on which is meshedthe chain 84 which also meshes with the sprocket 85 fixed to the shaft86 which has sprockets thereon that operate the conveyor II.

It is, therefore, quite apparent that I have invented a highly desirabledevice for the heretofore fully described purposes and which may beutilized to separate carbonaceous materials eificiently, dependably, andeconomically." Furthermore, the simplicity of the invention enables andassures its economical manufacture and, at the same time, minimizespossibility of the various parts of the invention getting out of orderor developing defects which are likely to prevent its usage or lessenits efiiclent operation.

While I believe that the form of the invention illustrated in thedrawings and referred to in the above description, as the preferredembodiment, is efficient and practical, yet realizing that theconditions concurrent with the adoption of the device will necessarilyvary, I desire to emphasize the fast that changes in the details may Thevalve II is likewise connected by a. link rod 82 by means of a bolt toany one of the 1 be resorted to, when required, without sacrificing anyof the advantages of the invention as defined in the claims.

For example, the impure or mined coal may be fed'onto the plate 58, andinto the tank I by any kind of conveyor or feeding device. The,pure coalconveyor 88 may be any conventional dsign, such as a single or doublechain with open metal flights. The refuse conveyor I! may be a ram orplate feeding to an elevator of either screw or bucket type, or flightconveyor. The circulating propellers may be placed at different anglesto the position shown to favor various conditions of installation, inwhich cases suitable housing or casing may be used The speed of thepropellers may be adjusted by any variable speed transmission deviceother than those shown, or the speed-changing devices may be discardedwhen the best speed for a particular constant operating condition isdetermined. Furthermore, the design of the plate 58, as well as thepartition 51 may be changed to meet various conditions.

What I claim as new and desire to secure by Letters Patent is:

1. In a device for separating mixtures of granular solids havingdifferent settling rates through a liquid and characterized by differentspecific gravities, the combination of a tank containing a liquid whosespecific gravity is greater than one and only moderately less than thesolid of .lower specific gravity said tank having an entrance side; abarrier extending across said tank approximately parallel with saidentrance side with its top substantially horizontal and below the liquidlevel in the tank and its lower margin above the bottom of the tank; aforaminous guide partition sloping downward from approxi: mately theliquid level along the entrance side of the tank toward the lower marginof said barrier from which it is spaced horizontally, the

'lower margin of the guide partition beingformed to produce with thebarrier a narrow approximately vertical throat; means for circulatingliquid in the tank from the space beyond the barrier beneath the barrierand then upward, part passing upward through said throat and part upwardthrough said foraminous guide partition, the structure being so arrangedthat the guide partition delivers any solids sliding down it into thethroat and the liquid flowing upward through the guide partition flowswith a substantial horizontal component toward the stream of liquidrising through the throat, and joining therewith, flows over thebarrier; means for feeding solids to be separated to the guide partitionat the entrance side of the tank; means for intercepting and withdrawingthe lighter granular solids which tend to settle in that part of thetank beyond the barrier; and other means for collecting and withdrawingfrom the bottom of the tank the heavier granular solids which settlethrough said throat.

2. In a device for separating mixtures of granular solidshavingdifierent settling rates through a liquid and characterized bydifferent specific gravities, the combination of a tank containing aliquid whose specific gravity is greater than one and only moderatelyless than the solid of lower specific gravity, said tank having anentrance side; a barrier extending across said tank approximatelyparallel with said entrance side and inclined upwardly and awaytherefrom with its top substantially horizontal and below the liquidlevel in the tank and its lower margin above the bottom of the tank; aforaminous guide partition sloping from approximately the liquid levelalong the entrance side of the tank downward toward the lower margin ofsaid barrier from which it is spaced horizontally, the lower margin ofthe guide partition being formed to produce with the barrier a narrowthroat; means for circulating liquid in the tank from the space beyondthe barrier, beneath the barrier and then upward, part passing rapidlyupwardthrough said throat and part less rapidly upward through saidforaminous partition, the structure being so arranged that the guidepartition delivers any solids sliding down it into the throat and theliquid flowing upward through the guide partition flows with asubstantial horizontal component toward the stream of liquid risingthrough the throat, and joining therewith, flows over the barrier; meansfor feeding solids to be separated to the guide partition at theentrance side of the tank; means for intercepting and withdrawinglighter solids which tend to settle in that part of the tank beyond thebarrier; and other means for collecting and withdrawing from the bottomof the tank solids settling through said throat.

3. The combination defined in claim 1 in which the lower end of theguide partition is imperforate and curved downwardly and in which thebarrier is curved at its upper portion away from the entrance side ofthe tank whereby the upper end of the throat formed between the guidepartition and the barrier is gradually flaring and consequently adaptedto minimize eddying while favoring horizontal flow away from theentrance side over the top of the barrier.

4. The combination with the structure defined in claim 1 of means for soadjusting said guide partition relatively to said barrier as to vary thewidth of the intervening throat.

JOEL R. BELKNAP.

